apisix/doc/plugins/syslog.md

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# Summary
- [**Name**](#name)
- [**Attributes**](#attributes)
- [**How To Enable**](#how-to-enable)
- [**Test Plugin**](#test-plugin)
- [**Disable Plugin**](#disable-plugin)


## Name

`sys` is a plugin which push Log data requests to Syslog.

This will provide the ability to send Log data requests as JSON objects.

## Attributes

|Name           |Requirement    |Description|
|---------      |--------       |-----------|
|host           |required       | IP address or the Hostname.|
|port           |required       | Target upstream port.|
|timeout        |optional       |Timeout for the upstream to send data.|
|tls            |optional       |Boolean value to control whether to perform SSL verification|
|flush_limit    |optional       |If the buffered messages' size plus the current message size reaches (>=) this limit (in bytes), the buffered log messages will be written to log server. Default to 4096 (4KB).|
|drop_limit           |optional       |If the buffered messages' size plus the current message size is larger than this limit (in bytes), the current log message will be dropped because of limited buffer size. Default drop_limit is 1048576 (1MB).|
|sock_type|optional      |IP protocol type to use for transport layer. Can be either "tcp" or "udp". Default is "tcp".|
|max_retry_times|optional       |Max number of retry times after a connect to a log server failed or send log messages to a log server failed.|
|retry_interval|optional       |The time delay (in ms) before retry to connect to a log server or retry to send log messages to a log server, default to 100 (0.1s).|
|pool_size    |optional       |Keepalive pool size used by sock:keepalive. Default to 10.|

## How To Enable

The following is an example on how to enable the sys-logger for a specific route.

```shell
curl http://127.0.0.1:9080/apisix/admin/consumers -H 'X-API-KEY: edd1c9f034335f136f87ad84b625c8f1' -X PUT -d '
{
    "username": "foo",
    "plugins": {
          "plugins": {
                "syslog": {
                     "host" : "127.0.0.1",
                     "port" : 5044,
                     "flush_limit" : 1
                  }
           },
          "upstream": {
               "type": "roundrobin",
               "nodes": {
                   "127.0.0.1:1980": 1
               }
          },
          "uri": "/hello"
    }
}'
```

## Test Plugin

* success:

```shell
$ curl -i http://127.0.0.1:9080/hello
HTTP/1.1 200 OK
...
hello, world
```

## Disable Plugin

Remove the corresponding json configuration in the plugin configuration to disable the `sys-logger`.
APISIX plugins are hot-reloaded, therefore no need to restart APISIX.

```shell
$ curl http://127.0.0.1:2379/apisix/admin/routes/1 -X PUT -d value='
{
    "methods": ["GET"],
    "uri": "/hello",
    "plugins": {},
    "upstream": {
        "type": "roundrobin",
        "nodes": {
            "127.0.0.1:1980": 1
        }
    }
}'
```